By using Wineskin Winery with the wrapper Wineskin-2.6.0 and the engine WS9Wine1.7.21, I was able to make this work. I told it not to use Mono, but instead installed .NET 2.0 with Winetricks.
And it's working! So far, the only odd bit I've found is that when autocomplete is turned on, as soon as you type the first l in llSay(), the app steals your focus away and you have to click to regain your focus and continue typing. That's rapidly going to become annoying. But still, it works! The other big drawback is that LSLEditor.app is 500mb. That's a lot of fat.
After that, I installed the command-line version of Wine with Mac Ports. Some people prefer Homebrew, but I don't know if it really matters as long as the tool does the job you're after. When it was finally done, I had Wine 1.6.4 installed. I then installed winetricks with ports, and added dotnet20. I did not install Mono.
From there, I could run: wine LSLEditor.exe
I had to run it twice, but it ran just fine after that.
I should also point out I'm on OSX 10.9.3 and before I'd always tried on 10.8.x, but I don't know if that has anything to do with it. And this version is 274mb, but it doesn't have to be the only Windows app in the Wine installation.
WineBottler does a similar trick, reusing Wine configurations, including the .wine one I just created in my home directory. And it has the added benefit of letting you run .EXE files directly from Spotlight. In my experience, it's also done a great job of extracting the correct icon for the app. It's my favorite setup, but can be difficult to configure. Wineskin's configuration tools are a lot clearer to understand.
=^.^=
